Fire hydrants require regular maintenance and must also be repaired. They are frequently installed on an even ground, or on lawns. For their repair or maintenance, the fire hydrant head must be lifted off the underlying upright feeding pipe which normally extends up to ground level. This is necessary in order to gain access to the valve normally installed in the pipe below the ground freezing level. Handling the fire hydrant head by hand is a tiresome operation which can freqently lead to injuries, due to the weight of these heads.
It is not always possible to back up a truck equipped with a hoist to the site of the hydrant, because of damage to the lawns or surrounding area. Moreover, such a truck is expensive to acquire and to operate. Hoists of the tripod type would also damage lawns.